Undoing after opening a bluperint will delete nodes in a math expression

Math expressions fail to compile when performing an Undo after opening a blueprint

ICE - wrong output link - ((1 + x) * (sin(myVar))) - (2.400000 / (rand()))

1. Open QAGame into UE4Editor
2. Open the BP_FunctionEventConversion blueprint
3. Press Ctrl + Z
4. Compile the blueprint

RESULT:
The blueprint fails to compile because a node in the math expression was deleted.